1. Field of the Invention
This invention relates to the field of equipment to assist in the performance of exercises.
2. Prior Art
The three elements involved in the performance of an exercise routine are the force of the exertion, the speed of the exertion, and the number of repetitions. There are many devices available for providing an appropriate force--barbells, rowing machines, springs, machines constructed with pulleys and weights, etc.--each device being configured to exercise particular muscle groups of the body. The stopwatch has received widespread use as a device for measuring speed of exertion, e.g., running speed over a given distance, swimming speed over a given distance, etc. Such measurements are applied to the timing of a number of exertions. However, this method of measuring speed informs the athlete of his speed only after the exercise has been completed.
For many years, physiologists and coaches believed that an athlete's so-called reaction time--the maximum time to contract a given muscle group--was determined primarily by genetic factors. The belief was held that an athlete's strength could be increased by performing resistance exercises but that his reaction time could not be affected significantly by traning. This widely held opinion has changed, however, and some coaches have adopted unusual approaches to training for faster reaction time. For example, some sprinters train with a ling rubber band which they stretch out on a field to distances of 50 meters. The runner sprints and is simultaneously pulled by the rubber band "to make his legs run faster". Another technique has been for an athlete to sprint while holding onto a moving automobile. There is nothing very quantitative about these methods however so their application has been limited.
A timing device which has arrived on the market place recently is the "Audostart". This device records the times required by an athlete to run the intervals of a distance by detecting his position with a photocell at each interval.
A training concept whose importance and practice has gained prominence in recent years is "isolation". By isolation is meant identifying one of the various muscle groups that are active in a given athletic maneuver and then performing exercise that "isolates" on that muscle group--that is an exercise in which that muscle group is the major group performing the exercise. For example, in sprinting, the muscle groups that are active include the hip flexors and extensors as well as the muscles of the calves, shoulders, back and abdomen. When an athlete sprints, the heart and lungs are the first to tire so that none of these groups are exerted to their capacity. Therefore, in order to build the hip flexors and extensors at maximum rate, an exercise is performed such as standing on one leg and bringing the second leg up and down at the fastest rate possible in order to fully exert the hip extensors and flexors of that leg.
Another aspect of the training phenomenon and the performance of athletic events is the onslaught of fatigue as the number of repetitions is increased with the result that the exercise is performed incorrectly. For example, when an athlete is performing the leg lift exercise as discussed in the previous paragraph, then as he tires, he fails to bring his knee up as high as required for optimum running form even though he may "believe" he is bringing his knee up. Furthermore, because of the differences in heights of the athletes, one athlete must bring his leg up to a different height than another athlete for proper performance of the exercise.
Other exercises that isolate on special muscle groups that are especially beneficial for developing sprinting speed are arm swings in which the legs are stationary. Again, when the arms are swinging and the legs are stationery, the cardiovascular and respiratory system does not tire so readily so that the swinging of the arms and shoulders can be exerted to maximum capacity.
Yet another aspect of the training phenomena is that, in the performance of very fast repetitions (such as stationery running drills or swinging the arms as if running) the athlete loses the count of his repetitions, and in any event, the extra chore of counting his repetitions at a very fast rate detracts from his ability to concentrate on increasing his rate of repetitions.
The principle of biofeedback has been used in a number of techniques to modify human performance. For example, it is well known that, with some practice, a human can change such functions as pulse rate, blood pressure, etc., simply by looking at the meter presenting the body measurement. Furthermore, it is widely accepted that if an athlete is able to measure his performance while he is performing the exercise, he is subjected to greater motivation to improve. This is the reason that an athlete generally runs faster in a race with other runners than by himself.
The exercises discussed in the foregoing paragraph were characterized by fast repetitions in which the beginning and ending position of each repetition was identical. The requirement for monitoring in this type of exercise is to be informed at the end of each repetition that the repetition has been completed within a desired interval of time so that the athlete can respond with greater effort as indicated while the exercise is in progress. Another type of exercise is where the athlete is performing a number of repetitions where the intention is not to complete a number of repetitions quickly but to perform each repetition quickly but to pause for a brief time between repetitions. For example, in a vertical jumping exercise, (such as for basketball players) the objective would be to jump as high as one can (as determined by the time off the floor) rather than how fast one can jump.
Still another type of monitoring is illustrated by a short sprint, where only one repetition is performed and the beginning and end positions are different. Furthermore, in this type of exercise, it is generally desireable to "hold" the monitor signal after the single repetition or event has been completed. For example, if a short sprint is completed in more than a preset time, this may be indicated by a light that would come on and stay on rather than simply flash briefly.
For the purpose of describing the invention, it will be useful to define and describe certain well known electronic components which are used in the construction of various embodiments of this invention.
A timer is defined to be an electronic component having a set of power terminals for receiving input power and one or more control switches. When power is applied to the power terminals, the control switches change state (open or close) for a period of time predetermined by a timer control, then revert to their initial state. In the context of this specification, terms "normally open" or "normally close" will refer to the initial state of the control switch before power is applied. With most commercial timers, the control switches are double throw, so that each switch has a "common" terminal and two additional terminals. In one switch position, the common terminal is connected to one terminal while in a second position, the common terminal is connected to the other terminal. The typical commercial timer has more than one control switch.
A delay line is defined to be identical to the timer except that the control switches remain in their initial state for a delay period after input power is applied and then switch to their second state and remain in that state until the input power is removed. The delay period is present by a manual control.
The delay line and timer are closely related components in the sense that for a particular application, the one may be substituted for the other with only minor modifications of the circuitry. This case of substitution provides for a number of means to accomplish the objectives of this invention as illustrated in the discussions that follow.
It is useful to differentiate further between the timer and the delay line by defining the signaling state of the control switch as being the position of the switch immediately after application of power and the state after the delay or timer period as the "nonsignaling" state. In accordance with this definition, the control switches of the timer are in the "nonsignaling" and the control switches of the delay line are in the "signaling" state when no power is applied to the power terminals.
Timers and delay lines of the type described are manufactured by the National Controls Corp., Lombard, Ill.
A photocell is defined to be an electronic component consisting of a light source that emits a beam of light and a sensor of the light beam. The sensor may be the retroreflective type wherein the sensor is located close to the light source and the beam crosses a distance where it is reflected back to the sensor. In the direct type, the sensor and light source may be located at opposite ends of the light path. The photocell may also have one or more control switches. Each switch of the typical commercial photocell is commonly a "double throw" switch and so has a common terminal and a first and second switch terminal. When the light beam is incident on the sensor, the switches will be in one state in that the common and first terminals will be connected whereas if the light beam is not incident on the sensor, then the switches are in the second state in that the common and second terminals are connected.
Photocells of the type described are manufactured by Microswitch a division of Honeywell, Minneapolis, Minn.
Yet another component that may be incorporated into various embodiments of this invention is the electronic stopwatch.
One type of electronic stopwatch will be referred to in this specification as a "pulsed" stopwatch. The "pulsed" stopwatch construction has a first, second and third stopwatch terminal and may be turned on or off if the first and second stopwatch terminals are connected momentarily. If the first and third stopwatch terminals are connected momentarily, the stopwatch time is reset to zero.
Stopwatches of the type described are distributed by DICK SMITH ELECTRONICS, with an office in Redwood City, Calif.
A second type of electronic stopwatch will be referred to in this specification as the "powered" stopwatch. This stopwatch is a pulse generator having an off-on terminal such that when power is applied continuously to the stopwatch terminals, a continuous stream of pulses is generated and the number of pulses is displayed as an indication of lapsed time. When the applied power is shut off (momentarily), pulse generation ceases and the generator is latched so that counting is not resumed after power comes on after the interruption
A electric counter is a component having a readout of numbers and a terminal for receiving electric pulses. When a pulse is received, the readout is increased by one digit. Means are also provided (usually as a push button) to reset the readout to zero manually.
Counters are manufactured by IVO Industries, Eatontown, N.J.
A latch is a combination of circuit elements with feedback which can be used to maintain power to a component such as when power is applied to the component through a momentary switch. One commonly used latch is a relay having a coil which closes a switch when energized. The relay switch is in parallel with the momentary switch. The relay coil is in series with the power source, the momentary switch and the component. When the momentary switch is closed, power is supplied to the component and the relay is energized so that the relay switch is closed. Even after the momentary switch is opened, power passes through the closed relay switch through the relay coil so that the relay switch is held closed. Power to the component is thereby maintained. In addition to relay latches, Integrated Circuit latches are also available from manufacturers of semiconductor deices such as National Semiconductor, Santa Clara, Calif.